Heat Exchange Device

ABSTRACT

Heat exchange device with a plate element ( 1 ) which has a shaped part ( 5 ) which extends over a heat exchange surface, is of at least partly flexible design and forms a partial boundary of a cavity ( 13 ), through which a heat transfer medium can flow and which is tightly closed off on the base side by a web ( 11 ) which forms on the heat exchange surface the contact surface for the heat transfer to a body ( 3 ), against which body the plate element ( 1 ) can be placed, wherein a flexible retaining plate ( 21 ) for pressing the plate element ( 1 ) against the body ( 3 ) rests on that top side of the shaped part ( 5 ) which is remote from the heat exchange surface on the base side, and wherein the flexibility of retaining plate ( 21 ) and the deformability of shaped part ( 5 ) and web ( 11 ) on the base side are selected in such a way that the plate element ( 1 ) can be adapted to the geometry of the body ( 3 ).

The invention relates to a heat exchange device having a plate elementwhich has a shaped part which extends over a heat exchange surface.

In mechanical devices, for example, machine tools, heat loss from drivesand highly loaded bearings as well as process-generated heat sourcescause temperature elevations in regions in bearing parts if no measuresto dissipate heat are taken. For high-precision machines, thedeformation which is caused by heating up of components adverselyaffects the dimensional stability of the workpiece in a profound way.Providing cooling as a countermeasure is often extremely difficult orcannot be carried out since structural circumstances preclude theintegration of cooling means such as holes or channels for a flowingheat transfer medium. Such holes of channels result not only in anadverse etfect on the bearing capacity of highly loaded components, butalso result in greater cost of the mechanical device.

With respect to the aforementioned, the object of the invention is tomake available a heat exchange device which is characterized by simpleconstruction, and yet enabling dedicated heat transfer at designatedlocations, as near as possible to the heat generating site or to atransition site to a thermally sensitive assembly.

This object is achieved according to the invention by a heat exchangedevice which has the features of claim 1 in its entirety.

Accordingly, the invention calls for a plate element in the form of aflexible cooling collar (or analogously a heating collar, to whichreference is made below), which conforms to the machine parts to becooled (or heated) and which due to flexible conformation forms a largecontact surface for heat transfer. In this way in-situ cooling is alsoenabled on components into which internal cooling systems cannot beintegrated. In addition, one special advantage is that the deviceaccording to the invention can also be added later. The device accordingto the invention can be of modular design and can be flexibly madelarger or smaller by attaching the desired number of plate elements orcollars and connecting them among one another, wherein the connectioncan be made as a parallel or series connection.

In advantageous embodiments the shaped part can be formed from anelastomer, preferably from nitrile rubber NBR. A shaped part such asthis on the one hand has the desired flexibility and on the other handis resistant to conventional heat transfer media, for example, towater-glycol and water with anticorrosion agents. Moreover, there isresistance to other fluids, such as oil, which can be found in thevicinity of mechanical systems.

The bottom-side web which tightly seals the cavity for the heat transfermedium against the shaped part and which forms the contact surface forheat exchange is formed by a film which has been made thin compared tothe wall thickness of the shaped part, preferably likewise from nitrilerubber NBR.

The retaining plate which rests on the top of the shaped part, in orderto apply a compressive force to the latter to press the plate elementagainst the pertinent body, is preferably formed by a thin metal plate.Its thickness can be chosen such that it enables, by hand, theadaptation of the plate element to the geometry of the body to becooled, but at the same time has a thickness such that it can transferthe necessary contact forces.

The arrangement can be made such that the heat exchange surface has arectangular outline which is rounded on the corner regions, theretaining plate extending superficially over the entire heat exchangesurface while exposing openings in the access regions for supply anddischarge of the heat transfer medium. The collar thus has the shape ofa closed, flat plate which is planar in the undeformed state, the planarsurface on the top being interrupted only by access openings for supplyand delivery of the heat transfer medium.

In advantageous embodiments the shaped part forms a plate with a planarsealing edge which extends continuously along the outside edge of theheat exchange surface and to which the bottom-side web is attached withthe formation of a seal, preferably by cementing, the plate in theregion within the sealing edge running offset away from the bottom-sideweb in order to form the inner cavity between the plate and thebottom-side web. In this way the space for the heat transfer mediumextends over the entire surface region of the plate, aside from theouter sealing edge, so that advantageously heat transfer can accordinglytake place effectively over a large area.

In especially advantageous embodiments, on the side of the plate facingthe bottom-side web, there are burls projecting into the cavity asspacers between the bottom-side web and the plate and for producingturbulence of the flow of the heat transfer medium. The burls, which canbe made in one piece in a large number on the shaped part, keep the filmprovided on the bottom-side web not only at a defined distance from theopposite wall of the cavity, but due to the generation of turbulencealso provide for good mixing of the heat transfer medium flowing intothe cavity and thus likewise contribute to an increase of efficiency.

Preferably the arrangement is such that the plate has a connectingbranch molded to the top for supply and discharge of heat medium intoand out of the cavity, the connecting branch penetrating the accessopenings which are made in the retaining plate which adjoins on the top.In this way there are simple connection possibilities for the lineswhich run on the outside of the pertinent body which is to be cooled,and connections between several plate elements can be formed withoutdifficulty.

Preferably the plate which forms the shaped part on its top in thecentral region above the cavity forms a planar contact surface for theretaining plate, on the sealing edge which extends along the outside ofthe heat exchange surface at least one bead being formed which projectson the top and which extends peripherally along the edge region in orderto cause an increase of the contact forces which are applied by theretaining plate and which act on the sealing edge.

The invention is detailed below using the drawings:

FIG. 1 shows a schematically simplified perspective oblique view of oneembodiment of the heat exchange device according to the invention, theplate element being shown in the state matched to one wall section of abody to be cooled and the wall section of the body being shown onlyschematically;

FIG. 2 shows a perspective oblique view similar to FIG. 1, an examplebeing shown with a plate element which is made more elongated relativeto FIG. 1 and which is matched to a circular cylindrical outside wall ofa body;

FIG. 3 shows a perspective oblique view in which the plate element madeaccording to FIG. 1 is shown in the undeformed state of a planar plate;

FIG. 4 shows a perspective oblique view, looking at the top solely ofthe shaped part of the plate element from FIG. 3;

FIG. 5 shows a perspective oblique view, looking at the underside of theshaped part from FIG. 4;

FIG. 6 shows a top view of the embodiment from FIGS. 3 to 5 shownapproximately at half the size of one practical embodiment;

FIG. 7 shows a section drawn approximately in natural size along lineVII-VII from FIG. 6;

FIG. 8 shows a section drawn approximately in natural size along lineVIII-VIII from FIG. 6;

FIG. 9 shows a cross section of the shaped part according to cuttingline IX-IX from FIG. 4, shown approximately on a scale corresponding toFIG. 4;

FIG. 10 shows a partial section of the region designated as X in FIG. 9,shown on a scale more or less doubled compared to natural size, and

FIG. 11 shows a perspective oblique view of one embodiment drawn on asubstantially smaller scale, provided with retaining clamps for placingthe plate element on a body which is not shown.

The invention is explained below using the embodiment of a coolingcollar through which a heat transfer medium can flow, for example, aconventional heat transfer fluid, such as water-glycol or water withanticorrosion agents, in conjunction with a coolant circuit which is notshown. As indicated briefly above, the exchange device according to theinvention could also be used as a heating collar for dedicated in-situheating of desired sections, the plate element being connected to aheater system and a heated heat transfer medium flowing through it.

FIGS. 1 and 2 illustrate application examples for which a plate element1 which forms a cooling collar is deformed for respective matching to awall section of a body 3, in the example from FIG. 1 the plate element 1being adapted to the staggered outside shape of the body 3. FIG. 2 showsone example in which the plate element 1 compared to the example fromFIG. 1 has a more strongly elongated shape and is adapted to a wallsection of a circular cylindrical body 3. Retaining means for placementagainst the body 3 are omitted in FIGS. 1 and 2, as well as theconnecting lines for supply and discharge of the used, flowable heattransfer medium.

The main component of the embodiment of the plate element 1, which is tobe described here and which is shown in its entirety in particular inFIG. 3 in an oblique top view and in the sectional views of FIGS. 7 and8, is a shaped part formed by a flexible plate 5 which is shownseparately in FIGS. 4 and 5 and which extends superficially over theentire heat exchange surface. The plate 5 has the outline of a rectanglewith rounded corner regions. As a comparison of FIGS. 1 and 2 shows, theoutline shape can be more or less elongated for adaptation tocircumstances. The plate 5, which acts as a shaped part in this example,is formed from an elastomer, in a special case from a nitrile rubberNBR. The use of such a material is advantageous in that there is bothsufficient flexibility for adaptation and conformation of the plateelement 1 to the corresponding contours, and there is also insulatingaction to the outside and resistance to the fluids under consideration.When the plate element 1 is made as a shaped part with a wall thicknessapproximately in the range from 3 to 5 millimeters, the necessarycompression strength, for example, for media pressures of approximately2 bar, also arises.

As is best shown in FIGS. 4, 7 and 8, the plate 5 on its top has planarwall regions which are offset to one another, specifically a centralpart 7 which extends along most of the plate surface and a sealing edge9 which surrounds the central part. As is especially apparent from FIGS.7 and 8, the planar central part 7 is offset relative to the surroundingsealing edge 9 such that a gap is formed between the plane defined bythe underside of the sealing edge 9 and the underside of the centralpart 7. Thus, when a tight termination is formed by a bottom-side web 11as a bottom-side termination on the underside of the sealing edge 9, inthe embodiment a film which is cemented to the underside of the sealingedge 9, then a cavity 13 which is used as a flow chamber for thepertinent heat transfer medium is formed in the gap region between theunderside of the central part 7 and the web 11. A plurality of burls 15are molded onto the underside of the central part 7 of the plate 5; theyare not all numbered in the figures and they project in the direction tothe web 11 within the cavity 13. These burls 15 form both spacerelements which keep the web 11 at a uniform distance from the opposingwall of the cavity 13 so that the web 11, with the plate 5 undeformed,runs in a common plane with the underside of the sealing edge 9, but theburls 15 also cause turbulence in the flow of the heat transfer mediumwithin the cavity 13; this causes good mixing and an increase of theefficiency of the heat transfer. On the underside of the sealing edge 9the web 11 is sealed, in addition to cementing, by means ofstrand-shaped sealing elements which are not shown in the drawings andwhich sit in grooves 17 which are made peripherally on the underside ofthe sealing edge 9.

Placed on the longitudinal center line of the rectangular shape of theplate 5, on the two end regions of the cavity 13 which border thesealing edge 9, that is, in the transition region between the centralpart 7 and the sealing edge 9, connecting branches 19 are made in onepiece with the plate 5 and extend perpendicular to the plane of theplate in the illustrated example. Depending on local circumstances andconnection conditions, these connecting branches, however, could also beprovided in a different tilt relative to the plane of the plate or couldbe made bent or angled. At the wall thickness of the shaped part whichis formed by the plate 5, which thickness remains essentially the sameover the plate surface, because the central part 7 to form the cavity 13is offset relative to the heat exchange surface which is defined by theweb 11 which adjoins the underside of the sealing side 9, a step isformed between the top of the central part 7 and the top of the sealingedge 9, as is apparent most clearly from FIGS. 7 to 9. As components ofa retaining means for pressing the plate element 1 which is used as thecooling collar against the pertinent body 3, there is a retaining plate21 in the form of a sheet metal plate with a wall thickness which ischosen such that manual deformation is possible for matching the plateelement 1 to the outside contour of the pertinent body 3. The retainingplate 21 which extends superficially with the same surface area as theplate 5 over the entire heat exchange surface has openings 23 which arealigned to the connecting branches 19 for passage of the connectingbranches. The retaining plate 21 which rests on the top of the planarcentral part 7 enables transfer of a contact force to the plate 5, forexample, using retaining clamps 25 which extend over the edge of theretaining plate 21 (FIG. 11).

For reliable operation care must be taken that the contact forceproduced by way of the retaining plate 21 is effective especially on thesealing edge 9. Since the top of the sealing edge 9, as alreadymentioned, is staggered relative to the plane of the top of the centralpart 7, that is to say, is offset relative to the plane of the retainingplate 21 which rests on the central part 7, between the top of thesealing edge 9 and the facing underside of the retaining plate 9, thereis an edge body 27 which constitutes a spacer body by way of which thecontact force is transferred from the retaining plate 21 to the sealingedge 9, see FIGS. 7 and 8.

As an additional special means for increasing the contact pressureacting on the sealing edge 9, on the top of the plate two annular beads29 and 31 are formed which project against the retaining plate 21 andwhose position can be seen most clearly from the highly enlarged detailfrom FIG. 10. For active contact force which is applied by way of theretaining plate 21 and the edge body 27 and for the resilience of theplate 5 which as the shaped part consists of an elastomer, the beads 29,31 in the operating state of the plate element 1 are pressed flat, seeFIG. 8. As FIG. 7 shows, only a short longitudinal section of theannular bead 29 in the region of the openings 23 for the connectingbranches 19 is exposed and therefore is not pressed flat at thislocation.

As already mentioned, for a wall thickness of the plate 5 which is usedas a shaped part and which for practical examples can be in the rangebetween 3 and 5 millimeters, there are both sufficient compressivestrength when it is an elastomer, such as NBR, and also deformability sothat the plate element 1 can be matched to the pertinent body 3 bydeformation of the retaining plate 21. The flexibility of the plateelement 1 is not adversely affected either by the bottom-sidetermination element which forms the contact surface, since in thisexample it is a flexible web 11 which can be thin-walled as a film, forexample, in the form of an NBR film.

The entire plate element 1 can be applied to the pertinent body 3 bymeans of a heat conducting paste in order to promote heat transfer.

1. A heat exchange device having a plate element (1) which has a shapedpart (15) which is at least partially designed to be flexible, whichextends over the heat exchange surface, and which forms the partialboundary of a cavity (13) through which a heat transfer medium can flowand which is sealed tight on the bottom by a web (11) which on the heatexchange surface forms the contact surface for heat transfer with thebody (3) against which the plate element (1) can be placed, resting onthe top of the shaped part (5) which faces away from the bottom-sideheat exchange surface, there being a flexible retaining plate (21) forpressing the plate element (1) against the body (3) and the flexibilityof the retaining plate (21) and the deformability of the shaped part (5)and bottom-side web (11) being chosen such that the plate element (1)can be adapted to the geometry of the body (3).
 2. The heat exchangedevice according to claim 1, wherein the shaped part (5) can be formedfrom an elastomer, preferably from nitrile rubber NBR.
 3. The heatexchange device according to claim 1, wherein the bottom-side web (11)is formed by a film which has been made thin compared to the wallthickness of the shaped part (5), preferably from nitrile rubber NBR. 4.The heat exchange device according to claim 1, wherein the retainingplate (21) is formed by a thin metal plate.
 5. The heat exchange deviceaccording to claim 4, wherein the heat exchange surface has arectangular outline which is rounded on the corner regions and whereinthe retaining plate (21) extends superficially over the entire heatexchange surface while exposing openings (23) in the access regions forsupply and discharge of the heat transfer medium.
 6. The heat exchangedevice according to claim 1, wherein the shaped part forms a plate (5)with a planar sealing edge (9) which extends continuously along theoutside edge of the heat exchange surface and to which the bottom-sideweb (11) is attached with the formation of a seal, and wherein the plate(5) in the region within the sealing edge runs offset away from thebottom-side web (11) in order to form the inner cavity (13) between theplate (5) and the bottom-side web (11).
 7. The heat exchange deviceaccording to claim 6, wherein on the side of the plate (5) facing theweb (11) there are burls (15) projecting into the cavity (13) as spacersbetween the bottom-side web (11) and the plate (5) and for producingturbulence of the flow of the heat transfer medium.
 8. The heat exchangedevice according to claim 7, wherein the plate (5) has connectingbranches (19) which are molded to the top for supply and discharge ofheat medium into and out of the cavity and which penetrate the openings(23) which are made in the retaining plate (21) which adjoins on thetop.
 9. The heat exchange device according to claim 8, wherein the plate(5) on its top in the region (7) above the cavity (13) forms a planarcontact surface for the retaining plate (21), and on the sealing edge(9) which extends along the outside of the heat exchange surface has atleast one bead (29, 31) which projects on the top and which extendsperipherally along the edge to increase the contact forces which areapplied by the retaining plate (21) and which act on the sealing edge(9).
 10. The heat exchange device according to claim 3, wherein the filmprovided as the bottom-side web (11) is connected by cementing to thesealing edge (9) of the shaped part (5).